Average schooling in US states is highly correlated with state wage levels, even after controlling for the direct effect of schooling on individual wages. We use an instrumental variables strategy to determine whether this relationship is driven by social returns to education. The instrumentals...

In the standard model of human capital with perfect labor markets general training. When labor market frictions compress the structure of wages in the general skills of their employees. The reason is that the distortion in the wage structure" turn technologically' general skills into specific'...